Mining machine



A. BALL.

MINING MACHINE.

APPLICATION FILED MAR. |2,'19|0. RENEWEDOCT- a, 1920.

1,403,829. N Patented Jan. 17,1922.

2vSH%/ M21885; Inventor.-

545M v alberi Ba -/m m/j I 5 A. BALL.

MINING MACH-INE. APPLICATION FILED MAR. 12. 1910. RENEWED OCT-8.1920.

1,403, 9 Patented-Jan. 17,1922.

2 SHEETS-SHEET 2.

UNITED stares PATENT GFFIE.

ALBERT BALL, GT GLAREIVZUNT, NEW HAIVIPSHIRE, ASSIGNOR, BY llIESNE ASSIGN- MENTS, TO THE JEFFREY IiZAI'IUTACTURING COMPANY, OF CQLUMBUS, OHIO,

A CORPORATION OF OHIO.

MINING MACHINE.

l,et03,829.

Specification of Letters Patent.

Patented J an. 17, 1922.

Application filed March 12, 1910, Serial No. 548,856. Renewed October 8, 1920. Serial No. 415,675.

in ining iiiiachines, of which the following descr )tlOll, in connection n the accompanyihg drawings, is a. specification, like letters on the: drawings representing like parts.

My invention relates to mining machines, more particularly intended to provide mproved means for feeding and guiding a mining machine while performing the cutting operation.

li ly invention ill be best understood by reference to the following description when tzlren in connection with the accompanying of, while its scope will be more particularly pointed out in the appended claims.

in the drawings:

Fig. 1 shows in plan partly broken away a minin" machine ei bodying one forn of my inven on;

Fig. 2 shows the same mining machine in sid elevation partly in section; and

5,, d, and are diagrams showing the machine or 1 as iii-ranged for the in .n cut, starting out and loadin moverespectively. neferring to the drawing have there disclosed for the suite of lustl tir one concrete form my invention, a m chine of the well-known cutter-chaprojecting therefrom d adapted to und ut the wall of the mine "'h a horla rf as the machine is 40 *ed transversely the direction of cutter hair length or in the direction shown by the arrow in 1.

The cutter bar, as usual, carries a suitable cutter chain 3, the lutt r moved by a 130WGT- driven sprocket wheel actuated y the vertically disposed electric driving root dis posed on the .me over the rear end of the cutter bar and adjacent the face. lhe details of the sprocket driving parts form no he eneral tvne of machine to which my nvention herein shown applied being disclosed in the prior patent to Mitchell No. 656,414.

While for such purposes any suitable construction may be employed, in the present machine supporting means are provided upon and with which the machine is adapted to move along the mine, and preferably, as

in the Mitchell patent referred to, in the form of a bottom member or shoe 5, upon which the machine is adapted to slide, if desired, directly upon the bottom or floor of the mine.

In order to hold the cutter chain and the cutter bar in the desired relation against the work as the machine is fed along, guiding means are provided, the same consisting of flexible guiding means herein comprising two ropes, cables or other flexible guiding members kept under tension and so associated with the machine that the cutter bar, as it travels, is held up to the work without the necessary use of rails or other like guiding supports.

In the illustrated form of my invent-ion I have provided for this purpose flexible guiding means, herein in the form of a wire rope or cable comprising two portions or lengths 6 and 7, each connected to a fixed support, one on the advancing side of the machine and the other on the receding side thereof, and one connected to the machine adjacent its wall or cutting end and the other nearer the opposite end thereof.

As seen in Figs. 1 and 2 the leading cable 6 on the advancing side of the machine cooperates with a feed operating member and herein is wound about a winding drum 8 adapted to cooperate with such a cable and herein mounted to rotate about an upright axis and preferably located. in rear of the front surface of the motor, herein at or adjacent the rear central portion of the machine and in rear of the motor. As shown in Fig. 1, the end of the cable which passes from its winding drum during the lateral feeding movement of the machine passes for ward longitudinally of the frame 1 to and about a guiding or directing sheave 9, the latter mounted to rotate about an upright axis near the front end of the body of. the machine on the advancing side thereof. While the free end of the leading cable might be fastened to its fixed support in advance of the machine, herein it passes to a suitably anchored guiding sheave 10 connected to the fixed support. or anchor 11 and thence back to the machine where it is fastened at 12. ll hile thus engaged by the fixed support at the anchor 11 it forms a double strand, making it possible to use a smaller cable for feeding the machine.

On the other hand, the trailing cable 7 on the receding side of the machine is adapted to cooperate with a take-up member and herein to be wound upon or unwound from a winding d-rum 13, the latter being adapted to be rotated by power, manually, or to rotate independently under the pull of a cable, and being herein arranged co-axially with and immediately above the winding drum 8 in rear of the motor, the axis of the take-up drum extending in the same direction as the axis of the drum 8 and, herein, also in the same direction as the axis of the motor. The cable 7 is suitably passed from the winding drum to the receding side of the machine and thence to a fixed support, or if desired to an adjustable take-up 14; (Fig. 3) similar to, the take-up jack in Figs. 16 and 17 of the aforesaid Mitchell patent.

The two cable portions (as represented in Figs. 1 and 3) may, therefore, be arranged in two substantially parallel lengths and, when under tension, with the cutter chain in position against the work, will serve to hold the cutter bar against the work and in a position which can be regulated by adjusting the trailing cable 7 to swing the machine more or less about the guiding sheave 9 as a fulcrum.

While the two cables 6 and 7 might be employed solely to guide the machine and hold the same in the desired relation to the work, other and independent means being em ployed positively to feed the machine, herein preferably I employ power-driven means to draw in one of the guide members while paying out the other, thereby to feed the machine at the same time it is guided. To this end both the winding drums 8 and 13 are connected to be driven in unison from the motor 4: so as to draw in one while equally paying out the other cable and to maintain the established tension on the two cables while causing the advance of the machine.

In the disclosed form of machine, in order to drive the drums the motor, through connections not herein shown, serves to drive the upright shaft 15, which latter drives a pinion 16 through an intermediate yieldable friction device 17. The latter is of welllrnown construction, and, having no essential relation to my invention, the details thereof are not shown. The driving pinion 16 meshes with a larger gear 18 which serves to turn the smaller pinion 19 (Fig. 1), the latter meshing with a larger gear 20. On the same shaft 21 (Fig. 2) with the gear 20 is the small drivingpinion 22 which meshes with the larger gear 23 secured to the winding drum 8. Through these connections the winding drum 8 is driven at a greatly reduced speed and through the intermediate friction l7.

Since the trailing cable herein has but a single run and its actual movement therefore should be only substantially half that of the leading cable, not only may the winding drum 13 be of a lesser width or winding capacity than the drum 8, but the movement of its effective winding surface should be substantially half that of the winding surface of the drum 8. This speed reduction may he obtained by other means, but herein the drum 13 is shown as having a. pitch diameter of substantially half of that of the drum 8 and during the cutting operation is driven at the same number of revolutions per minute as the drum 8. For I this purpose there is provided a well known 1 form of clutch device 2% adapted to be raised or lowered by suitable connections to the vertical slide rods 25 so as to protect its teeth through appropriate registering apertures in the walls of the drums 13 and 8, respectively. When the rods25 are raised the drum 13 is freed from the drum 8, but when the rods are lowered, it is clutched fast thereto. To control the clutch the upper ends of the rods are jointed to the arms 26 on't-he rock shaft 27, the latter adapted to be turned 7 by means of a shaft 28 controlled by the hand lever 29. By this arrangement and through the proportions of the drums the machine is so operated as to pay out the cable 7 while taking in the cable 6 at the same rate of speed or vice versa.

Referring to Fig. 3, the operation of the machine in effecting the lateral or main cut will be clear. As the machine cuts it is advanced by the winding in of the cable 6, which latter extends to the fixed supporting sheave 10 at the end of the coal face.

The cable 7, which extends to the fixed support 1ais paid out to an equal extent, so that the same cable tension is constantly maintained. The machine, therefore, as it travels, is held in and against the work, the cutters acting to draw the machine in and he trailing cable tending to swing the cutfor bar forward about the fulcruming guide sheave 9 and hold the cutters against the coal. 7 7' In the employment o machines of this class and particularly where wire or other cables have been-employed, great difliculty has been experienced from the fraying and wearing of the cables due to the great frictional wear brought uponthem. By arranging the winding drums, and particularly the drum for the leading cable, to rotate about an upright axis, I am enabled to employ a greatly increased diameter of drum, owing to the limitations which are imposed upon the height of such a machine, and I am enabled thereby greatly to reduce the frictional Wear of the cable against its drum, as well as to increase the drums capacity and reduce the number of convolutions required to be wound thereon. The drum being located near the rear of the machine the leading cable can pass therefrom to and about the guide sheave 9 with but slight angular deflection and ample room remains for constructing the guide sheave of such a large diameter as to reduce the frictional Wear imposed thereby upon the leading cable when under strain.

Suitable provision is preferably made to Wind on or unwind either cable from its drum independently of the motor, and without affecting the remaining cable. While this may be accomplished in any desired manner, herein there is provided a pinion 30 meshing with a gear 31 cut in the face of the drum 13 and adapted to be turned through the hand crank 32, so that when the latter drum is unclutched from the drum 8 the drum 13 may be turned by manual power independently of the motor and of the drum 8. To turn the drum 8 independently of the motor a separate gear 33 (see Fig. l) is employed which meshes with the large gear 23 on the drum 8 and may be turned by the hand crank 34:. By means of these attachments, therefore, either drum may be manually turned to take in or let out its cable without affecting the remaining drum.

In Fig. 4 I have shown the arrangement of the cable 6 which may be employed in effecting the starting or sumping cut. Herein this movement of the machine is shown as taking place from a starting frame frequently employed to guide a machine of this class, as its cutters enter the coal. F or this purpose the cable 6 passes from its winding drum to and about a guide sheave 36 fastened at the forward corner of the starting frame and thence back to the machine to Which its free end is secured. 'lhe winding in of the cable causes the machine to pull itself forward ofi from the starting frame and project its cutters into the face of the coal. v

In Fig. 5 the position of the cable is shown for loading the machine on to the starting frame or truck, or for hauling itself about the mine bottom. For this purpose the cable 7 passes from its drum to the rear end of the starting frame at 37 where its free end is secured so that the machine will haul itself on to the frame.

I do not herein claim the subjects matter of any of the claims in the Patent No. 1149110, issued August 3, 1915, on application Serial No. 548855, filed simultaneously herewith. In many respects the present mechanism is materially different from that therein. By my improved arrangement, it is possible for the feed operating member to cooperate with a flexible feeding member on the advancing side of the machine and thereby to cut closer to the rib. It is also made possible to reduce the length of the machine to a minimum, thereby making the machine adapted to close work. Further, in this embodiment, all the parts are arranged substantially concentric in relation to the central vertical longitudinal planes of the ma chine so that the apparatus is simplified, the parts are all arranged so as to be protected, none of them extending laterally to form projections liable to breakage and to interfere with the positioning of the machine to the best advantage in relation to the walls of the mine room.

The drums for the feeding and control cables are positioned at the rear end of the frame Where the devices for controlling the drums are readily accessible to the machine operator. The gearing is reduced to the smallest number of parts, the feeding and controlling drums being both mounted on a common vertical axis as described.

Claims.

1. In a mining machine, a machine frame slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor adjacent the face disposed over the front end of said frame and operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed operating member disposed on an axis in rear of the front surface of said motor and located in position to 00 operate with a flexible feeding member extending longitudinally of the advancing side of the frame, and a cooperating independently rotatable take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and likewise disposed in rear of the front surface of said motor.

2. In a mining machine, a machine frame slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom "above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor adjacent the face disposed over the front end of said frame and operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed operating member disposed on an aXis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member oi:- tending longitudinally of the advancing side of the frame, and a cooperating independently rotatable take-up member of smaller diameter rotatable on an axis extending in the same direction the axis of said feed operating member and likewise disposed in rear of the front surface of said motor.

3. In a mining machine, a machine frame slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor adjacent the face disposed over the front end of said frame and operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed operating member disposed on an axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member ex tending longitudinally of the advancing side of the frame, and a cooperating independently rotatable take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and disposed in advance of the rear end of said. frame.

4. In a mining machine, a machine frame slidable on its bottom on a mine bottom, a

cutter bar rigidly connected to said frame on said frame driven by said motor including a rotatable feed operating member disposed on an axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member extending longitudinally of the advancing side of the frame, and a substantially coaxially disposed cooperating independently rotatable take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and likewise disposed in rear of the front surface of said motor.

5. In a mining machine, a machine frame slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed operating member disposed on an axisin rear of the front surface of said motor and located in position to cooperate with a flexible feeding member extending longitudinally of the advancing side of said frame, a take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and likewise disposed in rear of the front surface of said motor, and means for rotating said take-up member independently of said feed operating member.

6. In a minin machine, a machine frame slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a. motor adjacent the face disposed over the front end of said frame and operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor i cluding a rotatable feed operating member disposed on an. axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member extending longitudinally of the advancing side of the frame, an independently rotatable take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and likewise disposed in rear of the front surface of said motor, and means for rotating said take-up member from said motor.

7. In a mining machine, a machine frame slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed operating member disposed on an axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding-member extending longitudinally of the advancing side thereof, a take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and disposed in rear of the front surface of said motor, and means for selectively rotating said take-up member from said motor or permitting independent rotation of said take-up member.

8. In a mining machine, a machine frame slidable on its bottom on a mine bottom, acutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed operating member disposed on an axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member extendin longitudinally. of the advancing side of the frame, a take-up member rotatable on an axis extending in the same direction as the axis of said feed operating member and disposed in rear of said motor, and means for selectively enabling simultaneous rotation of said members or independent rotation of said take-up member.

9. In a mining machine, a machine frame slidable on its bottom on mine bottom, a cutter bar rigidly connected to said frame and projecting thereirom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame in cluding a motor operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable fee-d operating member disposed on an axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member extending longitudinally of the advancing side of the frame, a take-up drum rotatable on an axis extending in the same direction as the axis of said feed operating member and disposed in rear of said motor, and means for enabling simultaneous winding in and out operations by different drums or rotation of said take-up drum in either direction independently of the other drum.

10. In a mining machine, a machine frame Slidable on its bottom on a mine bottom, a cutter bar rigidly connected to said frame and projecting therefrom above the bottom thereof, a cutter chain on said bar, cutter chain driving mechanism on said frame including a motor operatively connected to said chain at the rearward end of said bar, feeding mechanism on said frame driven by said motor including a rotatable feed op erating member disposed on an axis in rear of the front surface of said motor and located in position to cooperate with a flexible feeding member extending longitudinally of the advancing side of the frame, and a rotatable take-up member of smaller diameter than said feed operating member disposed in rear of the front surface of said motor and rotatable on an axis extending in the same direction as the axis of said motor.

11. A mining machine comprising a ma chine frame slidable on its bottom on a mine bottom and having a rigid cutter bar projecting therefrom, a cutter chain on said bar, a motor on said frame driving said cutter chain and disposed adjacent the face and over the front end of said frame, feeding mechanism on said frame including a rotatable feed operating member disposed on a vertical axis in rear of said motor and located in position to cooperate with a flexible feeding member extending longitudinally of the advancing side of the frame, a take-up member on said frame in rear of said motor and disposed on an axis extending in the same direction as the axis of said feed operating member, and means for selectively rotating one or both of said members.

12. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor gearing on which the frame is movable over the mine bottom, cut-- ting mechanism including a forwardly pro jecting cutter bar rigidly connected to said frame and a cutter chain movable around said bar, two drums mounted and rotatable on a common vertical axis at the rear end of said frame in the central vertical longitudinal plane thereof, a motor disposed on said frame in front of said drums and operatively connected thereto, flexible feeding members wound on said drums disposed in opposite directions at the front and rear of said frame, and a guiding means for one of said flexible feeding members disposed at the front of the frame and the other flexible member being adapted to be led directly laterally from its drum.

13. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and gearing on which the frame is movable over the mine bottom both laterally and also longitudinally while sumping, cutting mechanism including a forwardly projecting cutter bar rigidly connected to said frame and a cutter chain movable around said bar, two drums of different diameters both mounted and rota table on a common vertical axis at the rear end of said frame in the central vertical longitudinal plane thereof, a motor disposed on said frame in front of said drums and operatively connected thereto, flexible feeding members wound on said. drums and disposed in opposite directions at the front and rear of said frame, a guiding means for one of said flexible feeding members rotatable on a vertical axis and disposed at the front of the frame and the other flexible member being adapted to be led directly laterally from its drum.

ll. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and gearing on which the frame slides over the mine bottom both laterally and also longitudinally while sumping, cutting mechanism including a forwardly projecting cutter bar rigidly connected to said frame and a cutter chain movable around said bar, two drums of dif ferent diameters both mounted and rotatable on a common vertical axis at the rear end of said frame in the central vertical longitudinal plane thereof, a motor disposed on said frame in front of said drums and operatively connected thereto, flexible feeding members disposed in opposite directions at the opposite ends of said machine, the forwardly extending feeding member being wound on said larger drum and the rearwardly extending member being wound on said smaller drum, a guiding member rotatable on a vertical axis at the front end of the frame and engageable with said wardly extending feeding member and the other flexible member being adapted to be led directly laterally from its drum.

15. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and gearing on which the frame slides over the mine bottom both while it is movingilaterally and also while moving longitudinally, cutting mechanism including a forwardly projecting cutter bar rigidly connected to said frame and a cutter chain movable around said bar, two drums of different diameters both mounted and rotatable on a common vertical axis at the rear end of said frame in the central vertical longitudinal plane thereof,means for rotating said drums disposed in front of the ame, flexible feeding members disposed in opposite directions at the opposite ends of said machine, the forwardly extending feeding member bein wound on said larger drum and extendec from and returned to the machine and fastened thereto independently of the other drum and the rearwardly extending member being wound on said smaller drum, a guiding member disposed at the front end of the frame and engageable with said forwardly extending feeding member, a stationary take-up mechanism for said rearwardly extending flexible member adapted to be fastened in position at points remote from the frame, and a sheave engageable by said forwardly extending member at a point in advance of the machine.

16. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and gearing on which the frame is slidable over the mine bottom both while moving laterally and also while mov ing longitudinally, cutting mechanism on said frame including a forwardly projecting rigid cutter bar and a cutter chain moving around said bar, a motor mounted on the front end of said frame, two concentrically arn nged' drums both mounted on a common vertical axis and disposed in rear of said motor adjacent said shoe, driving connections between said motor and said drums, flexible feeding members wound on said drums disposable in opposite directions in front and rear of the frame, and a guiding member for one of said flexible feeding members disposed at the front of said machine, the other flexible member being adapted tobe led directly laterally from its drum.

17'. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and gearing on which the frame is slidable over the mine bottom both while moving laterally and also while moving longitudinally, cutting mechanism on said frame including a forwardly projecting rigid cutter bar and a cutter chain moving around said bar, a motor mounted on the front end of said frame, two concentrically arranged drums both mounted on a common vertical axis and disposed in rear of said motor adjacent said shoe and approximately in the central vertical longitudinal plane of the frame, driving connections including a yieldable friction disposed between said motor and said drums, flexible feeding members wound on said drums and disposed in opposite directions in front and rear of said frame, a guiding member for one of said flexible feeding members disposed at the front of said machine and the flexible member being adapted to be led directly laterally from its drum.

18. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and gearing on which the frame is slidable over the mine bottom both when moving laterally and also while moving longitudinally, cutting mechanism on said frame including a forwardly projecting rigid cutter bar and a cutter chain moving around said bar, a motor mounted on the front end of said frame, two concentrically arranged drums both mounted on a common vertical axis and disposed in rear of said motor and over said shoe approximately in the central vertical longitudinal plane of the frame, driving connections including a yieldable friction disposed between said motor and said drums, means for operatively connecting or disconnecting said drums, flexible feeding members wound on said drums and disposed in opposite directions in. front and rear ofsaid frame, and a guiding member for one of said flexible feeding members disposed at the front of said machine.

19. In a mining machine, a frame having a shoe rigidly attached'to the bottom thereof below the motor and gearing on which the frame is slidable over the mine bottom, both when moving laterally and when moving longitudinally, cutting mechanism on said frame including a forwardly projecting rigid cutter bar and a cutter chain movlng around said bar, a motor mounted on the front end of said frame, two concentrically arranged drums both mounted on a common vertical axis and disposed in rear of said motor and over said shoe and in approximately the central vertical longitudinal plane of the frame, driving connections including a yieldable friction disposed between said motor and said drums, means for operatively connecting or disconnecting said drums, flexible feeding members wound on said drums and disposed in opposite directions in front and rear of said frame, a guiding member for one of said flexible feeding members disposed at the front of said machine, and means for independently rotating one of said drums.

20. In a mining machine, a frame having a shoe rigidly attached to the bottom thereof below the motor and the gearing on which the frame is slidable over the mine bottom, both waen moving laterally and also while moving longitudinally, cutting mechanism on said frame including a forwardly projecting rigid cutter bar and a cutter chain moving around said bar, a motor mounted on the front end of said frame, two concentrically arranged drums, both mounted on a common vertical axis and disposed in rear of said motor and over said shoe and approximately in the central vertical longitudinal plane of the frame, driving connections including a yieldable friction disposed between said motor and said drums, means for operatively connecting or disconnecting said drums, flexible feeding members wound on said drums and disposed in opposite directions in front and rear of said frame, a guiding member for one of said flexible feeding members disposed at the front of said machine, and means for independently rotating each of said drums.

21. In a mining machine, the combination with cutting means, of flexible guiding means comprising a pair of flexible guiding members connected each to a fixed support one on the advancing side of the machine and the other on the receding side thereof, and connected to the machine, one near the wall or cutting end and the other nearer the opposite end thereof, co-axially arranged winding drums relatively adjustable to adjust the tension of said feeding members one relatively to the other and having different peripheral speeds when rotating and a speed reducing power transmitter for driving the drums simultaneously.

22. In a mining machine, the combination with cutting means, of flexible guiding means comprising a pair of flexible guiding members connected each to a fixed support, one on the advancing side of the machine and the other on the receding side thereof, and connected to the machine one near the wall or cutting end and the other nearer the opposite end thereof, and winding means for each of said guiding members each rotatable about an upright axis, said winding means being relatively rotatable to adjust the tension of said guiding members one relatively to the other.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

ALBERT BALL.

Witnesses:

HARVEY C.v BERKEY, Momus P. HOLMES. 

